Electro-magnetic relay



March 17, 1970 Filed Sept. 18, 1967 P'. R. ZWANEN HAL 3,501,722 ELECTED-MAGNETIC RELAY 2 Sheets-Sheet 1 FIG.3

FIG.3a

INVENTORS PETRUS R. zwm cu ANTON! DUTKIEWICZ AGENT Malich l 7, 1970 P. R. ZWA-NEN fAL 3,501,722

\ ELECTED-MAGNETIC RELAY Filed Sept 18. 1967 2 Sheets-Sheet 2 INVENTORS R. ZW A NEN PET RUS AGENT United States Patent 3,501,722 ELECTRO-MAGNETI'C RELAY Petrus Rumoldus Zwanen and Antoni Dutkiewicz, Emmasingel, Eindhoven, Netherlands, assignors, by mesne assignments, to US. Philips Corporation, New York, N.Y., a corporation of Delaware Filed Sept. 18, 1967, Ser. No. 668,324 Claims priority, application Netherlands, Sept. 17, 1966, 6613165 Int. Cl. H01h 3/28 US. Cl. 335-192 12 Claims ABSTRACT OF THE DISCLOSURE A relay comprising a U-shaped core and an L-shaped armature having its long limb extending approximately parallel and adjacent to one limb of the core. An S-shaped leafspring engages the armature at two areas spaced apart from the rotary axis of the armature. Between said two areas of engagement, a tag extending from said one limb of the core extends through an aperture in the leafspring and cooperates pivotally therewith.

The present invention relates to an electro-magnetic relay comprising a yoke provided with an energising coil and an armature, said armature being urged into its rest position by a leafspring and rotatably supported on an edge of the yoke and controlling an electric contact device.

In relays of the above type, it is customary to provide two spring members that cooperate with the armature, one of which retains the armature on a knife edge at the end of the yoke, whereas the other one urges the armature to its rest or deenergized position. The latter spring member, usually in the form of a leafspring, normally is arranged so that upon attraction of the armature by energization of the relay coil, the moment exerted by the leafspring upon the armature, which opposes the movement thereof, exhibits a substantial increase in value. This requires a relatively large amount of electrical energy to operate the relay.

The invention has for its object to provide a relay of the kind set forth which can be manufactured and assembled at comparatively low cost owing to the simple structure of the various parts. It comprises only one spring (said leafspring), holding the armature both on its knife edge support and urging it to its rest position. It is constructed so that the moment of the spring exerted on the armature can be made adjustable in a simple manner. A further advantage of the relay according to the invention is that when the armature turns out of its rest position, the moment exerted by the leafspring on the armature need vary comparatively little and may even de-- crease, whereas with known relays the moment increases generally to a greater or lesser extent. This slight variation of the moment is advantageous if it is desired to use a minimum of energizing power and an adequate contact pressure is wanted for break contacts in the contact device, i.e. contacts which are closed in the rest position of the armature.

According to one feature of the invention a relay of the kind set forth is characterized in that the leafspring extends transversely of the. rotary axis of the armature and engages the armature at two areas spaced apart from said axis. Between said areas the spring is shaped substantially in the form of an S so that at one area the leafspring co-operates pivotally with the armature and at the other area its face engages the edge of the armature extending parallel to the rotary axis. Between said areas of engagement with the armature, a part of the 'ice width of the leafspring co-operates pivotally with a stationary member forming part of the yoke. The plane going through the rotary axis and said edge of the armature extends more or less transversely of the part of the leafspring bearing on said edge. The length of the portion of the leafspring that extends between the stationary member and said one area of the leafspring exceeds the straight line distance therebetween. In an advantageous embodiment there are provided means, preferably in the form of an eccenter, for the adjustment of at least one area of co-operation of the leafspring and the armature and the yoke with respect to the other area.

According to a further feature of the invention the relay of the kind set forth is characterized in that the electric contact device is formed by stationary contact pins in an insulating plate and at least one contact member co-operating with the former and adapted to be moved by a catch coupled with the armature and displaceable parallel to the insulating plate, which member is formed by a hairpin wire extending parallel to the insulating plate. The bend of that wire is arranged loosely around one of the contact pins, while at least one limb extends along the other stationary contact pins and the catch has a stop for at least the other limb, by which stop in an end position the wire is urged against the pin surrounded by the bend and against the pin at the side of the first-mentioned limb. In an advantageous embodiment of this relay each of the limbs of the hairpin-like wire extends along a stationary contact pin located beyond the angle enclosed by the said wire, and a stop of the catch, also located beyond that angle, co-operates with each of the limbs of the wire, with which stop the limbs of the wire can be in contact by their own resilient force whilst the distance between the two stationary contact pins, along which the limbs extend, exceeds the maximum distance between the limbs, measured in the direction of the connecting line between said pins and admitted by the stops, while the bisector of the angle enclosed between the limbs of the wire is transverse of the direction of displacement of the catch.

The invention will now be described with reference to one embodiment formed by an angular armature relay. The embodiment is shown in the drawing, in which:

FIGURE 1 is a longitudinal sectional view of an angular armature relay taken as an example of the invention.

FIGURE 2 is a plan view of this relay,

FIGURE 3 illustrates diagrammatically the forces exerted by the leafspring on the armature in rest position after a given turn,

FIGURE 4 is an elevation of the electric contact device of this relay in which part of the insulating plate is omitted, and

FIGURE 5 is partly a transverse view and partly a sectional view of this contact device taken on the line V V in FIGURE 4.

The relay shown in FIGURES 1 and 2 comprises a U-shaped yoke 1. One limb of the yoke is formed by the magnetic core 3 provided with an energizing coil 2. The web of the U, together with the other limb, is formed by an L-shaped plate 4. The edge at the free outer side of this limb forms the rotary axis 5 of the armature 6, which also has the shape of an L, the short limb 7 of which co-operates with the magnetic core 3, whereas the long limb 8 extends approximately in the direction of the limb of the L-shaped plate 4 of the yoke. The inner angle of the angular armature 6 is urged against the limb of the plate 4 by a leafspring 9, extending transversely of the rotary axis 5, and co-operating with the armature at the areas A and B. The leafspring is curved between said areas substantially in the form of an S. The leafspring 9 is arranged in a recess 14 extending in the longitudinal direction of the long limb 8 of the armature 6. At the area A the leafspring 9 and the long limb 8 of the armature 6 co-operate pivotally so that this pivot may be free, but may also exhibit a certain amount of rigidity, or may even be clamped tight, it being assumed that the curved shape of the spring does not vary. At the area B, one face of the spring engages an edge 10 of the limb 8, extending parallel to the rotary axis 5. Between said areas A and B, the spring co-operates pivotally over part of its width with a tag 11 punched from the limb of the plate 4. The plane going through the rotary axis and the edge of the armature 6 is more or less transverse of the portion of the leafspring 9 bearing on the edge 10. The force of the spring 9 may be varied by means of an eccentric 12, which is arranged in the long limb 8 of the armature 6 and on which bears the edge 13, extending transverse of the longitudinal direction of the leafspring 9.

The leafspring 9 is prevented by the tag 11 from being displaced in the direction of the rotary axis and since this spring is engaged at the side between two shoulders 21 in the recess 14 of the long limb 8 of the armature 6, this armature is also prevented from displacing itself in the direction of the rotary axis. The web of the yoke 1 remote from the coil 2 bears on cams (not shown for the sake of clarity), forming part of an insulating plate 15, parallel to that web and having contact pins 16 fastened in it. These contact pins 16 may be arranged so that the relay can be mounted on perforated plates having printed wiring. Around the extension 17 of the angular armature 6 there is arranged a draw rod 18, which is adjustably connected with a catch 19, which is displaceable in parallel to the insulating plate 15. The catch 19 co-operates with a contact member 20, which is also displaceable parallel to the insulating plate 15.

It will be apparent from FIGURE 3 that at the area of its rotary axis 5 the armature 6 is urged against the yoke 1 by a force K which is the resultant of the forces K and K The spring 9 is curved so that the moments of the forces K and K act, at least in the rest position of the armature, in the same direction with respect to the rotary axis 5. The force K,, may be controlled by turning the eccentric 12. By a correct proportioning of the co-operative parts of the yoke 1, the armature 6 and the spring 9, it may be ensured that the sum of the moments of K and K with respect to the rotary axis 5 remains constant (or may even decrease) during the attraction of the short limb 7 of the armature 6, as is shown in FIGURE. 3. (The forces K and K remain substantially constant, whereas the arm of the moment of the force K subsequent to the attraction of the armature, is twice as great, and the arm of the moment of the force K is more than twice as low.) As a result, the energy required for energizing the relay is smaller than with the conventional structures which the overall moment increases. Even with the use of break contacts, suflicient contact pressure is obtained, even in the rest position of the armature.

In a practical embodiment the structure satisfies the aforesaid requirements with the values given in the FIG- URES 3 and 3a, the latter showing a developed view of the spring.

FIGURES 4 and 5 show how the long limb of the armature 6 displaces the draw rod 18 by means of an extension 17, said rod being adjustably coupled with the catch 19 by means of a spring 22 and a nut 23, the latter being screwed on the screw-threaded end of the draw rod 18. The catch 19 is adapted to move parallel to the plate and then displaces the contact members 20, each formed by a hairpin-like wire, the bend of which lies loosely around the contact pin 16a. The bisector of the angle between the hairpin-like wires is transverse of the direction of displacement of the catch 19. Each of the limbs of the hairpin-like contact members extends along a contact pin 16b and 16c respectively,

located beyond the angle enclosed by this contact member. Each of the limbs co-operate with a stop 24 and 25 respectively, also located beyond said angle, which stops may be engaged by the limbs by their own force of resilience. The distance between the two stationary contact pins 16b and 16c, along which the limbs extend, is greater than the maximum distance between the limbs, measured along the line of connection between these pins 16b and 16c and transmitted by the stops 24 and 25. The advantage of this structure is that the contact members can'be manufactured and mounted at low cost in a simple manner, and even if the available space is small the free length of spring may be great. By a suitable choice of the distance between the stops 24 and 25 a change-over contact or a make-before-break contact may be obtained.

In the rest position of the relay the contact members 20 are urged by the stops 24 of the catch 19 against the contact pins 16b. In the energized state of the relay the stops 25 exert pressure on the other limb of the contact members 20 so that the contact with the pins 16b is interrupted and established with the pins 160.

What is claimed is:

1. An electro-magnetic relay comprising a yoke provided with an energizing coil, an armature rotatably supported on an edge of the yoke and controlling an electric contact device, a leafspring extending transversely of the rotary axis of the armature and engaging the armature at two spaced apart areas so as to urge the armature into its rest position, the spring being shaped substantially in the form of an S between said two areas so that at one area the leafspring cooperates pivotally with the armature and at the other area its face engages an edge of the armature extending parallel to the rotary axis, a part of said leafspring located between said two areas of engagement with the armature pivotally engaging a stationary member connected with the yoke, the part of the leafspring bearing on said edge of the armature extending longitudinally in a direction transverse to a plane going through the rotary axis and said edge of the armature.

2. A relay as claimed in claim 1 wherein the leafspring is arranged so that, at least in the rest position of the armature, the moments of the forces exerted by the leafspring on the armature at said two areas act in the same direction with respect to the rotary axis of the armature.

3. A relay as claimed in claim 1 wherein the leafspring is arranged in a recess of the armature extending substantially in the longitudinal direction of the yoke, one edge of said recess forming the edge which is engaged by the face of the spring.

'4. A relay as claimed in claim 1 wherein the electric contact device comprises stationary contact pins arranged in an insulating plate and at least one contact member, co-operating with the former and movable by a catch coupled with the armature and displaceable parallel to the insulating plate, said member comprising a bent hairpin Wire extending parallel to the insulating plate, the bend of said Wire extending loosely around one of the contact pins so that at least one limb extends along a second stationary contact pin, and the catch comprises a stop for at least the other limb by which, in an end position, the wire is urged both against the pin surrounded by the bend and against the second pin.

5. A relay as claimed in claim 4 wherein the Wire is arranged so that the bisector of the angle enclosed by the Wire extends transversely of the direction of movement of the catch.

6. A relay as claimed in claim 4 wherein each of the limbs of the hairpin wire extends along a stationary contact pin located beyond the angle enclosed by that wire and in that a stop of the catch cooperates with each of the limbs of the wire, said stop also lying beyond that angle and engaging the limbs of the wire by the natural resilience of said limbs, the distance between the two stationary contact pins, along which the limbs extend, being greater than the maximum distance between the limbs measured at the area of the line of connection between these pins and transmitted by said stops.

7. A relay as claimed in claim 4, characterized in that in its direction of moment the catch is adjustably coupled with the armature.

8. A relay as claimed in claim 1 wherein said armature further comprises an adjustable member that engages an end portion of the leafspring, said member being adjustable to vary the linear distance between the area at which the leafspring engages the adjustable member and the area at which the leafspring engages said edge of the armature.

9. A relay as claimed in claim 8 wherein said adjustable member comprises a screw and an eccentric cam engaging said end portion of the leafspring.

10. A relay comprising a magnetic yoke, an energizing coil coupled to said yoke, an armature pivotally supported on an edge of the yoke and controlling an electric contact device, an S-shaped leafspring having its longitudinal axis extending transversely to the axis of rotation of the armature and engaging the armature at two spaced apart areas differently spaced from said axis so as to urge the armature into its rest position, a part of said leafspring between said two areas being in pivotal engagement with a stationary member forming part of the yoke, said leafspring, at the area nearest the axis of rotation, having its face contacting an edge of the armature that extends parallel to said axis of rotation, the longitudinal axis of said leafspring at the latter area being substantially transverse to a plane passing through said edge of the armature and said axis of rotation, said leafsprin g, at the contact area 6 furthest away from said rotation axis, pivotally cooperating with the armature, the length of the leafspring extending between said furthest area and said stationary member exceeding the straight line distance therebetween. 11. Arelay as claimed in claim 10 wherein said yoke comprises a U-shaped member and said armature com- ,prises an L-shaped member having its long leg extending -approximately parallel and adjacent to one leg of the U-shaped member, said armature leg having a longitudinal recess in which a substantial part of the leafspring is positioned.

12. A relay as claimed in claim 11 wherein said leafspring includes an aperture through which said stationary member protrudes.

References Cited BERNARD A. GILHEANY, Primary Examiner H. BR'OOME, Assistant Examiner Us i 33 5-20; 

